The present invention relates to gas turbine engines. In particular, the present invention relates to cooled components for gas turbine engines.
A gas turbine engine commonly includes a fan, a compressor, a combustor, a turbine, and an exhaust nozzle. During engine operation, working medium gases, for example air, are drawn into and compressed in the compressor. The compressed air is channeled to the combustor where fuel is added to the air and the air/fuel mixture is ignited. The products of combustion are discharged to the turbine section, which extracts work from these products to produce useful thrust to power, for example, an aircraft in flight.
The compressor and turbine commonly include alternating stages of rotor blades and stator vanes. Compressor and turbine rotors include stationary annular fluid seals surrounding the blades and acting to contain and direct the flow of working medium fluid through successive stages. Compressor and turbine rotor seals, sometimes referred to as outer air seals, commonly include arcuate seal segments circumferentially arranged to form a ring about the engine axis radially outward of the blades. The outer air seal including the ring of arcuate segments is attached to the engine case by, for example, one or more support rings.
The operating temperatures of some engine stages, such as in the high pressure turbine stages, may exceed the material limits of the seal segments and therefore necessitate cooling the segments by using, for example, compressor bleed air directed to the segment through, for example, the support rings. Cooled seal segments may include cooling features such as film cooling holes, internal cooling passages, and impingement cooling plates. Increasing the effectiveness of internal cooling passages is a common challenge in rotor seal design. Prior rotor seals have struggled to increase the filling of internal cooling passages with cooling fluid flow. In particular, prior art seals have exhibited inadequate filling toward the cooling passage end walls adjacent the axial inter-segment surfaces where adjacent seal segments adjoin.